Sustainable Water Management and Environmental Resilience

Inhaltsverzeichnis

1. Frontmatter

2. Chapter 1. Assessment of Hydrologic Alteration for the Ganges River in Bangladesh: A Pre and Post Farakka Barrage and Treaty Scenario

   Md. Reaz Akter Mullick, Shyamal Acharya, Md. Hazrat Ali, Md. Abu Sayed, Saima Zaheen

   Abstract

   This study investigates the hydrological alteration of the Ganges River in the context of three distinct periods: pre-Farakka (1960–1975), post-Farakka (1976–2019), and the post-Ganges Water Sharing Treaty (GWT) period (1997–2019) using Indicators of Hydrologic Alteration (IHA) software. The Ganges River, shared by India, China, Nepal, and Bangladesh, is vital for the socio-economic and environmental well-being of the region. The Barrage at Farakka that was constructed in 1975 altered the natural flow of the Ganges, impacting downstream riparian country Bangladesh. Despite a water sharing agreement in 1977 and subsequent treaties, unilateral withdrawals by India persisted, leading to major impact to the downstream riparian as well as river health. With the historical discharge data of the Hardinge Bridge point the IHA software was used to assess the hydrologic alteration for the Ganges River in Bangladesh. Results show that some improvement has been achieved in post treaty period regarding river hydrology. The Hydrologic Alteration (HA) in pre-treaty period was 59 whereas in post-treaty period the HA is 55. However, Environmental flow parameters are suffering significantly in the post Farakka period. The findings contribute valuable insights for policymakers seeking to balance water sharing, economic needs, and ecological sustainability in the Ganges basin.

3. Chapter 2. Isotopic and Hydrogeochemical Evaluation of Ganges and Jamuna Floodplain Aquifers in Bangladesh: Integrated Water Quality Index and Health Risk Appraisal

   Md. Moniruzzaman, Hafiz Al-Asad, Hazzaz Bin Hasan, Ratan Kumar Majumder, Shamim Ahmed, Md. Abdul Quaiyum Bhuiyan, Md. Ariful Ahsan

   Abstract

   Developing countries and the global population face a significant challenge in ensuring an adequate supply of fresh groundwater. Human activities have had a detrimental impact on groundwater, which is a crucial source of fresh water. Currently, there is growing apprehension regarding the presence of nitrates (NO₃⁻) and trace metals (As, Cr, Ni, Pb, and Fe) in groundwater due to the extensive use of fertilizers and other human-made sources like sewage or industrial wastewater discharge. Thus, this study assesses hydrochemical characteristics that influence groundwater quality, assessing contamination levels, recharge mechanisms, and potential health risks of the Ganges Floodplain (GF) and Jamuna Floodplain (JF) in Bangladesh. A total of 105 water samples were gathered and analyzed, encompassing chemical parameters, trace metals, and isotopic composition to calculate groundwater quality. The findings indicated that the standard allowable limits WHO are exceeded by the concentrations of NO₃, As, Cr, Ni, Pb, Fe, and Mn in the shallow and intermediate aquifer, while it is lower at the deep Holocene aquifer of GF and JF. Water types prevalent in the GF and JF are primarily Ca–HCO₃ to Na–HCO₃ types. The results of δ¹⁸O and δ²H showed how precipitation has recently recharged the Floodplain regions. The PCA was employed to discern pollution sources and controlling factors, revealing that groundwater quality is primarily influenced by geological factors and various anthropogenic activities. The IWQI indicates that groundwater from shallow aquifers is deemed unsuitable for drinking purposes in both the GF and JF. In contrast, deep Holocene aquifers are found to be suitable for drinking. Additionally, the majority of shallow groundwater samples highlight remarkable levels of pollution in JF and GF according to the HPI, HEI, and CD values. It is possible to conclude that the results of a comprehensive investigation will alert decision-makers and the local populace, empowering them to implement efficient management strategies to protect groundwater resources in Bangladesh and mitigate potential health risks for the residents.

4. Chapter 3. Assessment of Pollution and Water Quality of Coastal Seawater of Saint Martin’s Island

   Imtiaz Ahmed Sakib, Ferdousi Begum, Adiba Mosharraf, Farhana Akter, Md. Arman Hossain, S. K. Rahat Rezwon, Md. Abu Bin Hasan Susan

   Abstract

   Saint Martin’s island, located at the southernmost tip of Bangladesh, has significant ecological value for being most favourite tourist spot and acting as a nesting site for many internationally vulnerable marine species. This island’s marine biodiversity is exceptionally wealthy due to its favorable environment, but its marine environment is facing threats day by day due to natural calamities, various types of pollution, and other anthropogenic activities. This study was conducted on Saint Martin’s Island, through assessing the quality of seawater collected from 9 stations, determined using the Global Positioning System. Various physicochemical properties: pH, conductivity, total dissolved solids, turbidity, salinity, density, viscosity, refractive index and dissolved oxygen with concentration of phosphate and nitrate were measured. Concentration of arsenic, lead, mercury, zinc, sodium and magnesium were also investigated by Atomic Absorption Spectrophotometer and the trend of average concentration of mineral and heavy metals was Na > Mg and Zn > Pb > Hg > As, respectively. Furthermore, several water quality indices were calculated for physicochemical parameters and concentration of heavy metals where category of seawater quality was found “Good” according to Canadian Council of Ministers of Environment (CCME) Water Quality Index (WQI) and Weighted Arithmetic (WA) Water Quality Index (WQI) revealed “poor” quality. Thus, seawater quality parameters have been critically analysed, correlated and essential findings were noted and. Obtained results highlight variation in most of the seawater quality parameters of Saint Martin and have a good correlation with each other.

5. Chapter 4. Assessment of Potential to Improve Water Quality in Natural Wetlands: A Case Study in Kotagala Natural Wetland, Nuwara Eliya, Sri Lanka

   J. M. A. U. Jayasekara, N. D. K. Dayawansa, M. I. M. Mowjood

   Abstract

   Wetlands are essential for purifying water, but human activity poses serious risks to many of them. This study investigates the removal efficiency dynamics of the Kotagala natural wetland in Nuwara-Eliya, Sri Lanka, which is increasingly endangered by encroachment and untreated effluent discharges. There is a need to better understand the factors influencing the efficacy of wetlands in contaminant removal under varying environmental conditions. To address this, we utilized a general removal efficiency equation to calculate removal efficiency values. Then descriptive statistics and P values were used to analysis the data statistically. Temporal analysis of removal efficiencies shows significant deviations from the general trend, particularly in the removal of phosphate and nitrate. Analysing the impact of monthly precipitation on removal efficiencies reveals a positive relationship between wet months on EC, TSS, Nitrate and Phosphate. On the other hand, salinity and TDS exhibit negative correlations with precipitation. All the p values associated with the different parameters shows the less values than significant level which is 0.05. It concludes, there is a significant relationship in between the removal efficiencies and the rainfall fluctuations. Regardless challenges, the Kotagala wetland exhibits potential for improving water quality, highlighting its importance as a natural remedy further study reveals that rainfall is not only factor influence on the nutrient removal efficiencies.

6. Chapter 5. The Bangladesh Erosion Monitor: Automatic Detection of Riverbank Erosion and Its Potential Use for Project Planning

   Imran Khan, Arjen V. Haag, James Lilly, Kymo Slager, Md Shahadat Hossain, Raqubul Hasib, Morsheda Begum, William Oliemans, Zahirul Haque Khan

   Abstract

   The Bangladesh Erosion Monitor (BEM), developed through the Google Earth Engine platform using JavaScript, is a novel tool designed to assess erosion and accretion in Bangladesh’s major river systems. Utilizing the extensive historical records of the Joint Research Centre (JRC), this approach conducts a comprehensive planform change analysis. It intricately blends data covering administrative boundaries, essential infrastructures, the dynamics of water flow, and patterns of global land use. This integration offers a multi-faceted perspective on how river systems evolve and interact with both the natural environment and human-developed landscapes. This approach aids in understanding erosion impacts and supports informed decision-making. Including actionable information for policymakers, the tool identifies vulnerable infrastructure like embankments and ferry terminals, estimates potential damages to agriculture and households from river erosion, and can perform a scenario analysis to calculate inundation depths in breached coastal polders. Its multifaceted data layers enable users to predict and strategize against the adverse effects of riverbank erosion and flooding. Validated against real-time riverbank survey data, this tool represents an advancement in the field of environmental risk management by effectively implementing geospatial technology in novel new ways. It provides valuable insights for policy development, especially in addressing river erosion and flood hazards in Bangladesh, thus contributing meaningfully to the field.

7. Chapter 6. Prediction of Stream Bank Failure at Paturia Ferry Ghat of Padma River of Bangladesh in Terms of Bank Materials

   Uma Saha, Fatima Rukshana, Nayan Chandra Ghosh, Md. Moniruzzaman, Sumiya Ferdhous, Bikash Roy, Kazi Rezaul Karim

   Abstract

   This study has been undertaken to predict the bank failure mechanism of Padma River at Paturia ferry ghat of Bangladesh regarding bank materials. In this context, laboratory test results of soils and water levels were analyzed. From the analysis, it has been observed that the low flood level at Paturia ferry ghat varies from 1.8 to 2.0 mPWD at which the bank materials are non-cohesive. However, the high flood level varies from 7 to 9 mPWD which exceeds the bank elevation of bank line 6.667 to 6.935 mPWD, where the materials from the bank line to the ground surface are cohesive layers containing 30% clay. The presence of such clay particles creates a higher level of bonding among the other particles which are more resistant to surface erosion because of their lower permeability. These soils are more susceptible to bank failure during the rapid drawdown of water levels due to the increases in pore pressures which lead to tension cracks. The study results will inform the design engineer about the bank failure mechanism; however, a comprehensive geotechnical investigation will be needed prior to the design for the protection of the Paturia ferry ghat.

8. Chapter 7. Estimation of Braided River Bathymetry by Data Fusion Method for Hydro-morphological Simulation: Applicability for the Riverbank Erosion

   Mohammad Muddassir Islam, Shampa, Israt Jahan Nejhum

   Abstract

   Riverbank erosion by the Brahmaputra-Jamuna River has displaced thousands of people from their homes and pushed them into abject poverty in Bangladesh. Consequently, a better system for predicting riverbank erosion might be one tactic to mitigate the consequences of such a disaster. Numerical simulation of riverbed evolution can be a solution of that which necessitate high-resolution bathymetry data. The river bathymetry measurements taken by the Bangladesh Water Development Board (BWDB) at 4–6 km intervals are too coarse for numerical simulation. An appealing alternative to the costly and time-consuming classical bathymetric mapping of braided rivers is the data fusion of measured data with spectral reflectance obtained from satellite images. The data fusion method was used to construct 10 m resolution river bathymetry using sentinel 2 images and limited measured data. The estimated bathymetry has been evaluated for the adequacy of river erosion estimation using a 2D hydro-morphological model for the years 2017–2019. On average, between 2017 and 2019, the estimated bathymetry showed a depth of 10, 9, or 10 m, with a maximum depth of 17.5, 16, or 19.5 m. The simulated model’s R2 value was close to 0.96 in relation to a discharge at Bahadurabad. The NSE, PBIAS, and RRMSE for the Mathura, Bahadurabad, Serajgani, and Chilmmari stations, respectively, show the level of satisfaction. Kappa statistics was used to measure the accuracy of erosion predictions, and the results for the three years 2017–2019 were around 67%, 78%, and 72%, respectively.

9. Chapter 8. Experimental Investigation on Minimizing Erosion Near the First Groin in a Series Within a Channel

   Md. Tofiquzzaman, Mohammed Alauddin

   Abstract

   Groins are common hydraulic structures built in series to safeguard river banks. The stability of the groins and the protected zone depends on the stability of the first groin of a series. Despite the abundance of literature on groin design, groin effect, and so on, a few studies have focused on reducing thrust on the first groin due to upstream flow. This study explores a suitable approach to minimize the impact of upstream flow on the groins placed in a series focusing on the stability of the first groin. The study considers three different options: a set of five impermeable groins in a series (Case-1); the first one is a combined groin of Case-1 (Case-2); and an additional upstream minor combined groin in Case-1 (Case-3). All the laboratory experiments are conducted in this study under clear-water scour conditions. The results revealed that the first groin of combined nature in the series as well as the minor combined groin upstream of the main groins reduced the effect of upstream flow significantly. Compared to Case-1, Case-2 and Case-3 showed 50% and 47% reduction of scour, respectively. Therefore, Case-2 has been identified as an effective way of stabilizing groins and river banks in the field.

10. Chapter 9. Assessing Water Insecurity for Bankline Communities Considering Riverbank Erosion: A Case Study Along the Padma River

    Lamiya Sharmeen Jaren, Sabbir Ahmed, Syed Nazmus Sakib, Sara Nowreen, Ahmed Ishtiaque Amin Chowdhury, Rabeya Sultana Leya

    Abstract

    The concept of water security includes a diverse range of physical, socio-economic, environmental, and infrastructural water related challenges, traditionally measured by the Water Security Index (WSI). This study presents a disaster management inclusive approach for measuring WSI at the household level. The objective of this study is to assess water insecurity for bankline communities considering river erosion in selected unions in Harirampur, Manikganj, along the river Padma. By employing a mixed-method approach encompassing remote sensing, structured questionnaire survey of households, and participatory techniques, various indicators of water security were evaluated. WSI were calculated by using weighted additive function where component weights were assigned by pairwise ranking method through expert opinion. The results showed that the WSI value was 44.25, classifying the area as water insecure. The system is considered water secured when the WSI value is greater than 56. The scores for the components of WSI, basic household needs, food production, environmental flows, risk management, and independence were 46.87, 69.1, 33.33, 39.37, and 34.27, respectively. Approximately 43.24 km² river eroded, and 17.00 km² river accreted in last two decades. Multiple frequencies of homestead shifting occurred among respondents which had a negative impact on water security. Moreover, the study identified risk factors contributing to water insecurity, such as inadequate disaster preparedness and erosion control measures. Based on these insights, a sustainable framework for addressing water insecurity in erosion-prone areas is proposed which provides actionable recommendations for enhancing resilience and sustainability in water management practices.

11. Chapter 10. Assessing Spatial Thresholds of Indices-Based Water Mapping with Sentinel-2 for Ukhia and Teknaf of Bangladesh

    Saifullah Sayed, Sara Nowreen

    Abstract

    Efficient water planning crucially relies on monitoring surface water resources. In this context, threshold-based index methods are a less complex yet accurate approach to separate waterbodies from satellite imageries. Therefore, this study aims to identify efficient water mapping methods by comparing the performance of various water indices on Sentinel-2 scenes in the Eastern Hills (EH) of Bangladesh, using it as a case study. Here, the popular indices NDWI, MNDWI, NDMI, WRI, AWEInsh, AWEIsh, NWI, and SWI, are assessed. While finding the best panchromatic band, SWIR1 has been found to have a strong association (R² = 0.512) with the average of four bands: Red, Green, Blue, and NIR. Similarly, VNIR and SWIR2 are found to be strongly correlated with the Red Band with R² values of 0.68 and 0.43, respectively. High Pass Filter has the highest Universal Quality Index, lowest Spectral Angle Mapper, and lowest Root Mean Squared Error for pan-sharpening SWIR1, SWIR2, and VNIR bands. NDWI shows the highest Kappa (0.87) and F1-score (0.92). Following historical (2016–2023) analysis, Yen thresholding method shows an overall accuracy ranging from 82% in 2023 to 96% in 2021. Thus, the study suggests using Yen thresholding for NDWI in EH of Bangladesh.

12. Chapter 11. Assessing and Evaluating the Water Security: Water Quality, Accessibility, Availability, and Sanitation Practices Among the People of Sultanpur Village, Raozan, Chattogram

    Sadia Salim, Sayed Mohammad Nazim Uddin

    Abstract

    Groundwater is the only major source of potable water in Bangladesh. The concepts of quality, availability, accessibility, sanitation, and hygiene practices of drinking water all play a role in water security. This study evaluated the state of water security of Sultanpur village of Raozan Upazila, Chittagong through conducting a total of 210 household surveys, 4 Focus Group Discussions, 7 Key Informant Interviews, and lab tests to identify the issues at the grassroots level and contributing to the national development. The study's findings demonstrated that the water quality has deteriorated; people suffer from severe water scarcity, inaccessibility, sanitation, hygiene, and health issues. Other than pH, manganese (Mn), lead (Pb), and temperature, the parameters did not meet the drinking BD and WHO water standards. The survey and laboratory test results showed that excessive iron (highest = 21.08 mg/l) and low dissolved oxygen (2.3 mg/L) level posed health risks for the local population. This research emphasizes the urgent need for improved water resource management and alternative solutions to address the water security issues in Bangladesh.

13. Chapter 12. Impact of Dasherkandi Sewage Treatment Plant on Balu River and Intake of Saidabad Water Treatment Plant

    Rajib Ahmed, Sazia Afreen, Md Mizanur Rahman

    Abstract

    Megacity Dhaka spanning around 401 km² currently accommodates nearly 22 million people. Although the city has 5 peripheral rivers-Turag, Buriganga, Balu, Shitalakshya, and Dhaleswari; Dhaka WASA (DWASA), the authority providing water supply and sewerage facilities, is now forced to pump raw water from the Meghna and Padma rather than the aforementioned because of the deterioration of water quality which results in high operational costs. DWASA’s Saidabad Water Treatment Plant (SWTP) (450 MLD) is pumping raw water from the Sarulia intake point of the Shitalakshya River. Meanwhile, Dasherkandi Sewage Treatment Plant (DSTP) (500 MLD) was established to reduce the pollution in the Balu River and eventually to improve the influent quality of SWTP. This study aims to assess the impact of DSTP on the Balu River and Sarulia intake. Water quality parameters such as DO, COD and NH₃–N were tested on samples collected from 11 potential sources. The study found that although the effluent quality of DSTP is within the Department of Environment (DoE) Standards, the influent quality of the Sarulia has not improved significantly due to untreated discharge from the industries along the Balu and Shitalakshya Rivers. The study suggests shifting SWTP intake to a nearby feasible upstream location.

14. Chapter 13. Water, Sanitation-Hygiene Security of Urban Slum Dwellers During Covid-19 Pandemic: An Insight from Rajshahi City Corporation

    Shehan Tawsif, Shitangsu Kumar Paul, Md. Shohel Khan

    Abstract

    Covid-19 pandemic has influenced the water, sanitation-hygiene security around the world. The current study aims to discover water, sanitation-hygiene (WASH) security of urban slum dwellers during covid-19. Rajshahi City Corporation slums were categorized into inner, middle and outer slum zones to conduct the study. Total of 361 slum household were determined as a sample population at 95% confidence level. A pre-tested semi-structure questionnaire was formulated to conduct household data collection. Data was collected from June–September 2022 and were analysed through SPSS and map was produced by ArcGIS 10.4 software. Study revealed that overall 37.5% respondent used mask to remain safe in pandemic. About 61.5% of the slum dwellers share one tube well and outer slum zone dweller were found higher (79.5%). About 53, 43.3 and 36.7% of outer, middle and inner zone dwellers use common toilet. Major defecation facility of inner slum dwellers was water sealed latrine (47.8%), followed by 24.5 (outer) and 10% (middle). The study also revealed that inner slum zone dwellers were highly (0.74) secured to WASH security and middle and outer zone dwellers were moderately secured. This study reflects that WASH practice needs to be more enhanced in slum communities to combat pandemic situation.

15. Chapter 14. Solarine: A Solar Panel-Aided Efficient and Automatic Rooftop Rainwater Harvesting System Using Arduino

    K. M. Sadman Sakib, Nazmush Shahadot Safin

    Abstract

    Bangladesh endures recurrent water scarcity because of its geographical and climatic qualities. The traditional water supply infrastructure cannot handle the increased demand for potable water. Rainwater collection is a sustainable and ecologically aware alternative to traditional water procurement methods. The combination of this technology and rooftop solar panels is a fresh and inventive approach to solving Bangladesh's concurrent water and energy problems. In Bangladesh, there is little literature on rainwater collection, and scholarly research on the integration of this technology with rooftop solar panels is rare. Rainwater collection can provide a sustainable and viable water source in both urban and rural Bangladesh, according to empirical findings. This is where our hypothesis comes from, which is, combining the traditional solar panels in a v-shaped pattern can turn it into an effective rainwater catchment area, which can increase the harvest amount of rainwater greatly. Performing small scale experiments and analysing the captured data thoroughly, we have found our hypothesis is true, and combining solar panels as a v-shaped catchment area actually increases the harvest of rainwater. This study gives us the empirical proof that using this innovative idea helps significantly in both urban and rural areas for RRWHS along with solar energy conversion.

16. Chapter 15. Effectiveness of Using Water Hyacinth and Submerged Aerator to Accelerate the Ammonia-Nitrate Conversion in Trimohoni Area

    Anannya Ghosh Tusti, Rizwanur Rahman, Md. Delwar Hossain

    Abstract

    The rapid population growth and uncontrolled pollutant discharge through various point and non-point sources have endangered the water body of Trimohoni, Dhaka. The water restoration here is necessary to support economic activity, sustainability, and ecological balance. The industrial and domestic waste mixed with Trimohoni’s water has caused eutrophication, resulting in algal bloom, loss of DO and aquatic species, and high turbidity. The case-controlled study assessed the efficiency of integrated use of aeration and phytoremediation for higher efficiency in improving several water quality parameters within 5 days in the laboratory setup. The reactor with water hyacinth and submerged aerators had greater ammonia–nitrogen (AN) conversion efficiency (93.9%), which was 2.3 times better than using only submerged aeration and 3 times better than natural aeration. The water quality also got better in terms of BOD, COD, TDS, and turbidity. The reactor with water hyacinth and submerged aerators was consistently seen to work very well. For better performance and further successful implications, a real-life, large-scale assessment is recommended.

17. Chapter 16. A Sustainable Waste Management Model for Passenger Ships in Bangladesh: A Step Towards Climate Change Adaptation

    Md. Mahmudul Hasan Akib, Zobair Ibn Awal, Mohammad Tanvir Hossain

    Abstract

    Bangladesh’s river network of almost 230 rivers, serves as crucial transportation routes for millions of passengers annually. Despite ratifying international conventions on marine pollution, Bangladesh lacks a National Marine-Environmental Protection Policy. Therefore, dumping untreated waste into water bodies has become habitual due to the absence of monitoring of effluent-releasing standards. This research aligns with the urgent need for a sustainable waste management model in the maritime sector, considering the inadequate waste management practices and the country’s vulnerability to climate change. The proposed model integrates a biogas-composting plant within a passenger ship and a plastic segregation chamber. This innovative solution addresses organic waste from ships, generating biogas for cooking, a sustainable alternative to LPG. The plastic segregation chamber facilitates the proper storage and sale of plastic waste for recycling, fostering a circular economy and reducing the demand for new plastic production. Aligned with multiple Sustainable Development Goals (SDGs), the research promotes environmental protection, energy independence through biogas, and a more resilient infrastructure. It aims to reduce greenhouse gas (GHG) emissions and improve air and water quality by solving the longstanding waste management challenges in the maritime sector of Bangladesh.